When you do a SBC swap, you normally install a new balancer and will need a new timing pointer. It is best to get these setup while the engine is out of the car and you can better determine TDC.
For this swap, I was able to keep the timing tab on the timing cover, so I just added a new white mark on the balancer.
For this one, I added a new pointer off one of the bolt holes and notched, notched the balancer and filled the notch with white paint. When all you have is a single reference point, then it is best to use a timing light with an adjustment dial. You turn the knob to line up the two point, then read the setting on the knob to determine the actual amount of timing.
For this one, I made the notch on the archie bracket about 3 o clock and one on the balancer. This one can be read from the wheel well using the same timing light with a dial.
Some people used to make a mark on the flywheel and bottom of the timing case and time the engine from underneath...
So as long as you have a timing light with an adjustment dial, you can put the timing mark in just about any position you want, as long as it precisely located TDC.
